Since childhood lead poisoning first gained recognition as an important public health problem, the concept of lead poisoning has been examined and revised repeatedly. This national conference was convened to review and examine the current state of the problem, prevention activities, and recent studies on the toxic effects of lead at very low levels. Papers presented at the conference focused on the following topics: (1) changing sources of lead poisoning; (2) national perspectives; (3) overview of low-lead toxicity; (4) low-level exposure and children's development; (5) U.S. Department of Housing and Urban Development regulations; (6) the Environmental Protection Agency's perspective on lead in water, gasoline, and soil; (7) regional collaboration; (8) laboratory issues; (9) environmental issues; (10) legal issues; (11) lead used as treatment in folk medicine and other nonpaint sources of lead; and (12) future directions. (JD)